Re-lubrication is an essential part of machine maintenance, particularly when the machine comprises rolling element bearings. Commonly, the bearings are mounted in a housing that is equipped with a lubrication point for supplying the bearing with grease. When the lubrication points on a machine are located in a hard-to-reach place, automatic lubricators are often connected to the lubrication points. If, however, the lubrication points are accessible, it is common practice for these lubrication points to be lubricated manually.
A maintenance technician may print out a task list of machines and associated lubrication points where a prescribed quantity of grease is to be delivered, when the prescribed re-lubrication interval has elapsed. A grease gun is typically used, possibly in combination with a grease flow meter, to ensure that the correct quantity of grease is delivered. When each lubrication task on the list has been completed, the technician will then enter the associated data in, for example, a lubrication scheduling program.
A problem associated with manual lubrication is that lubrication points are not always clearly indicated on a machine, making it possible to lubricate the wrong place. Also, the entry of data after all of the lubrication tasks have been performed incurs the risk of errors. A machine which had not, in fact, been re-lubricated might get marked as such in the program, meaning that the next scheduled lubrication action will occur too late.
A possible solution to this problem is proposed in U.S. Pat. No. 6,997,286, which discloses a method and a device for the manual lubrication of a plurality of lubrication points with a quantity of lubricant, individually predetermined for each lubrication point. The lubrication points are provided with individual identification elements. Information on the quantity of lubricant to be administered to each lubrication point in each instance of lubrication is stored in a memory. During lubrication, the lubrication point is identified and information on the predetermined quantity of lubricant is retrieved from the memory, following which lubricant is administered to the lubrication point. Information on the lubrication carried out and the time thereof is stored in the memory. The device includes a lubricant gun, with means for measuring the quantity administered and for identifying the lubrication point.
Although this solution eliminates many of the possibilities for human error, the cost and effort involved in providing each lubrication point with an electronic identification tag is considerable.
Consequently, there is room for improvement in terms of defining a method and a system for executing a manual re-lubrication plan, which are more straightforward and inexpensive.